Comparison of Experimental and Computational Ice Shapes for a Swept Wing Model 2011-38-0093
Two-dimensional and three-dimensional leading edge ice shapes for a finite wing model computed with the NASA Glenn LEWICE 2.0 and LEWICE3D Version 2 ice accretion codes are compared with experimental data from icing tunnel tests. The wing model had 28° leading edge sweep angle, 1.52-m (60-in) semispan and an airfoil section representative of business jet wings. Experimental wing leading edge ice shapes were obtained at the NASA Glenn Icing Research Tunnel (IRT) for six icing conditions. Tests conditions included angles of attack of 4° and 6°, airspeeds ranging from 67.06 m/s (150 mph) to 111.76 m/s (250 mph), static air temperatures in the range of -11.28°C (11.7°F) to -2.78°C (27°F), liquid water contents of 0.46 g/m₃, 0.51 g/m₃, and 0.68 g/m₃, and median volumetric diameters of 14.5 μm and 20 μm. In the experimental investigation, four glaze ice shapes with complete scallop features were obtained using progressively longer ice accretion times (2, 5, 10, and 22.5 minutes) to provide a range of horn sizes. Also, a 10-min incomplete scallop glaze ice shape, a 22.5-min glaze ice accretion representative of an ice protection system failure case, and a 5-min rime ice shape were generated. Aerodynamic and icing analyses were performed for the six cases investigated during the icing tunnel tests. Generally, the analytical ice shapes were observed to have greater vertical extents between the ice horns and smaller ice growth in the chordwise direction than their experimental counterparts.